California State Route 203
state highway in Mono County, California, United States
State Route 203 is a state highway in the U.S. state of California that serves as a spur route from U.S. Route 395 in Mono County to the town of Mammoth Lakes and Minaret Summit. Within Mammoth Lakes, State Route 203 is known as both "Minaret Road" and "Main Street." It connects to Lake Mary Road and the Mammoth Scenic Loop via secondary roads.
Route description
Route 203 is defined in section 503, subsection (a), of the California Streets and Highways Code, and that the highway is "from the Mono County line near Minaret Summit to Route 395". In addition, subdivision (b) permits the state to relinquish control of the portion of Route 203 located within Mammoth Lakes to the town.
SR 203's western terminus is at Minaret Summit, on the border of Mono County and Madera County approximately 7 miles northeast of Devils Postpile National Monument. It then heads east and intersects with Mammoth Scenic Loop Road, before entering the town of Mammoth Lakes, where it is known as both "Minaret Road" and "Main Street". It continues east to its eastern terminus at U.S. Route 395.
West of SR 203's western terminus, the road continues locally as "Postpile Road" or "Minaret Summit Rd" for 8.5 miles passing Devils Postpile National Monument and ending at Red's Meadow Resort and Pack Station. East of US-395, the road continues for 1.7 miles as "Old Hwy" connecting utility yards and rural residences to the route.
Minaret Summit receives significant snowfall during the winter.
“California State Route 203” enters the record as state highway in Mono County, California, United States. Crown Archives preserves that source wording while asking what California, State and Route can confirm, complicate or overturn.
Why this record matters
“California State Route 203” is worth following because a concise public description often conceals a longer documentary argument. Here, California, State and Route provides the most credible route into that argument.
Place names and jurisdictional language are key evidence: both can reveal earlier catalogue descriptions and overlooked record series. The source revision retrieved here is dated Sep 13, 2026. The linked authority identifier is Q805308. Authority coordinates are 37.649, -118.982. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
Architectural summaries often privilege surviving fabric and can understate demolished phases, contested use or displaced communities. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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Three-step research path
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This entry incorporates text from “California State Route 203” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.